Here, the acceleration field is physically the same as the gravity field, and because the acceleration field in the present invention is generated by a centrifugal force, it may be referred to as a centrifugal field or a centrifugal acceleration field. Also, a strong (high) acceleration field is referred to as a high acceleration field, a high-gravity field, a supergravity field, or a supercentrifugal field.
Due to the energy situation and the highly-developed communication industry in recent years, the importance of isotopes such as energetic isotopes typified by U and Pr for atomic fission, and tritium and 6Li for tritium for atomic fusion, high-performance semiconductors composed of Be, C, B, Na, K, Cs, Mg, B, Al, Si, Ge, Co, Fe, Ga, As, P, Sb, Zn, In, Bi, Sn, S, Se, F, CL, I, O, N, and the like, quantum semiconductors composed of Be, C, B, Na, K, Cs, Mg, B, Al, Si, Ge, Co, Fe, Ga, As, P, Sb, Zn, In, Bi Sn, S, Se, F, CL, I, O, N, and the like, and medical isotopes typified by C, N, O, F, Cr, Ga, Br, Tc, I, Au, Tl, Br, In, La, Eu, Gd, Dy, Ho, Yb, Lu, Re, and the like has increased. As methods of enriching isotopes, there are electromagnetic method, gas diffusion method, gas centrifugal method, nozzle separation method, thermal diffusion method, laser method, cryogenic method, plasma method, and chemical exchange method. For the purpose of industrial manufacturing, the gas diffusion method and the gas centrifugal method are mainly used.
In nuclear fuel business, the isotope enrichment is regarded as the most important part in a nuclear fuel cycle which includes mining, refining, and enriching nuclear fuel material. Therefore, nuclear energy development and utilization starts with uranium enrichment, and, in the uranium enrichment technique, low-cost and operational safety are important.
The gas diffusion method is employed in United States and France, and uranium hexafluoride (UF6) of corrosive gas is the material. The separation coefficient at a single-stage is approximately 1.003, and a large-scale cascade is set up in order to obtain enriched uranium with a concentration of 3 to 4%. In this method, corrosive gas, low separation coefficient, and high-cost caused by the large-scale facilities are pointed out as issues.
The gas centrifugal separation method is employed in Japan, United Kingdom, and Holland, and UF6 is the material. The separation coefficient is expected to be 1.4, and a cascade is set up in order to obtain enriched uranium. In this method, corrosive gas, and high-cost caused by the large-scale facilities are still pointed out as issues. The laser method is regarded as a future technique together with atom method and molecular method, and the development has been continued in various countries.
In Patent Document 1 as a related art literature, a high-speed rotation test apparatus is disclosed. However, the main point is on the temperature control of a rotor at a time of the high-speed rotation, and it has no relation to the present invention. Patent Document 2 is a related art literature related to the invention by one of the inventors of the present invention, and an apparatus and a method for diffusion process by using centrifugal field of condensed material are disclosed. However, the invention of separating and enriching the condensed material composed of a plurality of isotopes are neither disclosed nor suggested. In Patent Document 3, although a multistage apparatus by a centrifugal rotor is disclosed, the disclosure is about no more than a simple liquid distributor, and separation and enrichment of a plurality of isotopes as in the present invention are neither disclosed nor suggested.    Patent Document 1: Japanese Unexamined Patent Publication No. 2003-103199    Patent Document 2: Japanese Unexamined Patent Publication No. Hei-9-290178    Patent Document 3: Japanese Unexamined Patent Publication No. 2004-130182